Build Error, Undefined reference to [function]
Hi, so I have written a program to help me learn virtual methods, and I get an error every time i build it, saying:
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<path>\12-10_DataSlicingWhenPassingByValue.o:12-10_DataSlicingWhenPassingByValue.cpp|| undefined reference to `PtrFunction(Mammal*)'|
||=== Build finished: 1 errors, 0 warnings ===|
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even though I have clearly defined the function and implemented it
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#include <iostream>
using namespace std;
class Mammal
{
public:
Mammal():itsAge(1) {}
virtual ~Mammal() {} //I suspect destructor needs to be virtual so that the derived class's destructor can be called?
virtual void Speak() const {cout<< "Mammal speak!\n"; }
protected:
int itsAge;
};
class Dog : public Mammal
{
public:
void Speak() const {cout<< "Woof!\n";}
};
class Cat: public Mammal
{
public:
void Speak() const {cout<< "Meow!\n";}
};
void ValueFunction(Mammal);
void PtrFunction(Mammal*);
void RefFunction(Mammal&);
int main()
{
Mammal* ptr = 0;
int choice;
while(1)
{
bool fQuit = false;
cout<< "(1)dog (2)cat (0)Quit: ";
cin >> choice;
switch (choice)
{
case 0: fQuit = true;
break;
case 1: ptr = new Dog;
break;
case 2: ptr = new Cat;
break;
default: ptr = new Mammal;
break;
}
if (fQuit == true)
break;
PtrFunction(ptr);
RefFunction(*ptr);
ValueFunction(*ptr);
}//end while
return 0;
}
void ValueFunction(Mammal MammalValue)
{
MammalValue.Speak();
}
void PrtFunction(Mammal* pMammal)
{
pMammal -> Speak();
}
void RefFunction(Mammal & rMammal)
{
rMammal.Speak();
}
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Is there something I am doing wrong?
Thanks in advance.
Edit: I have just realized this should probably be in beginner's forum, my apologies
Last edited on
Spot the spelling mistake :-)
*facepalm
thanks!
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